Have you ever picked up a package labeled “biodegradable” or “compostable” and wondered what the difference really is? You’re not alone.
These two buzzwords are everywhere—from grocery bags to toothbrushes to food containers. But while they sound similar (and eco-friendly), they don’t mean the same thing. Understanding what they actually mean—and how they break down in the environment—can help you make better choices for the planet and avoid falling for greenwashing.
Let’s break it down (literally and figuratively) so you can shop smarter and feel good about your impact.
First, Why Does It Matter?
Americans generate over 292 million tons of municipal solid waste every year according to the US Environmental Protection Agency, and a big chunk of that ends up in landfills, where very little breaks down efficiently. Even items labeled as “green” or “earth-friendly” often don't degrade the way we expect them to.
Knowing the difference between biodegradable and compostable can help reduce your environmental footprint and keep unnecessary waste out of landfills.
What Does “Biodegradable” Really Mean?
At its core, “biodegradable” means that a material can be broken down by microorganisms like bacteria or fungi into natural elements—carbon dioxide, water, and biomass.
Sounds great, right? But here’s the catch: there’s no set timeline for when something biodegrades. It could take weeks, years, or even decades, depending on the material and environment.
Important point:
A biodegradable product thrown in a landfill (where oxygen and microbes are limited) may not actually break down for decades.
Also, not all biodegradable items are non-toxic. Some can leave behind residues or microplastics—especially if they’re made from synthetic materials.
Quick takeaway:
“Biodegradable” is vague. It’s not a guarantee the product will break down quickly or safely.
What Does “Compostable” Mean?
Compostable materials are a type of biodegradable—but they’re held to stricter standards.
To be labeled “compostable,” a product must break down into non-toxic components (like water, carbon dioxide, and organic matter) within a specific timeframe and under certain conditions. It also must not leave any visible, distinguishable, or toxic residue behind.
There are two main types:
- Home compostable – breaks down in your backyard bin.
- Commercial compostable – requires higher heat and specific conditions found only in industrial facilities.
In the U.S., products that meet compostability standards often carry certifications like:
- ASTM D6400 for plastics (ASTM International)
- BPI-certified compostable from the Biodegradable Products Institute (BPI)
Quick takeaway:
Compostable products are biodegradable, but not all biodegradable products are compostable.
Biodegradable vs Compostable: A Side-by-Side Look
|
Feature |
Biodegradable |
Compostable |
|
Breaks down naturally? |
Yes |
Yes |
|
Timeframe for breakdown? |
Undefined |
Defined (usually under 180 days) |
|
Leaves toxic residue? |
Possibly |
No |
|
Requires specific conditions? |
Sometimes |
Yes (home or industrial composting) |
|
Certified by third parties? |
Rarely |
Often (e.g., BPI, ASTM) |
So Which Is Better?
If you’re trying to reduce waste and environmental harm, compostable products are the safer bet—but only if you have access to composting.
If a compostable item goes to landfill, it might not break down properly. Landfills are low-oxygen environments, so both biodegradable and compostable materials can take a long time to degrade—or may even release methane, a potent greenhouse gas.
That said, biodegradable products can still be useful—especially if composting isn’t available—just be sure to look for specifics about what the product is made of and how long it takes to break down.
Watch Out for Greenwashing
A product labeled "biodegradable" can be misleading if there’s no explanation of what that means.
Some items claim to be biodegradable but are made with oxo-degradable plastics, which break down into smaller pieces but not into safe organic matter. These tiny plastic bits—called microplastics—can contaminate soil and water. That’s not exactly what we’re going for.
Tips to avoid greenwashing:
- Look for third-party certifications (BPI, OK Compost, ASTM).
- Read the label carefully—does it say how or where to dispose of the item?
- Check if it's made from 100% plant-based or organic materials.
- When in doubt, reach out to the company or do a quick online search.
Easy Actions You Can Take Today
Making more sustainable choices doesn’t have to be hard or expensive. Here are simple ways to put this knowledge to use:
1. Start a Compost Bin
Even a small indoor compost bin for food scraps and compostable items can reduce your landfill waste significantly. Check out How to Compost at Home by EPA to get started.
2. Switch to Certified Compostable Products
For things like trash bags, utensils, and food containers, look for items certified by BPI or meeting ASTM D6400 standards.
3. Say No to Unverified “Biodegradable” Plastics
If it sounds too good to be true, it might be. Stick with materials like bamboo, organic cotton, paper, or other compostable-certified goods.
4. Learn What Your Local Composting Facility Accepts
If your city offers curbside composting or has a drop-off site, find out what materials they accept. Not all commercial facilities take packaging or utensils.
Try tools like Find a Composter to locate one near you.
5. Support Companies That Use Honest Labeling
Vote with your wallet. Support brands that are transparent about their materials and disposal instructions.
Fun Facts to Impress Your Friends
- A compost pile can reach up to 160°F—hot enough to kill weed seeds and pathogens, which is why some items require commercial composting.
- Plastic bags labeled “biodegradable” can still last years in a landfill.
- Composting at home can reduce your carbon footprint by up to 50%, depending on your waste stream (Project Drawdown).
What to Look For When Shopping
Next time you shop for a “green” product, here’s a checklist to use:
- Does it say biodegradable or compostable?
- Is there a certification like BPI or ASTM D6400?
- Are there instructions for proper disposal?
- What is the product made of—natural materials or synthetics?
Final Thoughts
Biodegradable and compostable products aren’t just trendy labels—they have real environmental implications. Now that you know the difference, you can make more informed decisions that align with your values and help move us all toward a lower-waste future.
It’s not about being perfect—it’s about being intentional. One smart swap or composted fork at a time, you’re helping create a cleaner, greener world.
Photo by Julia M Cameron on Pexels.